Alterations in Polysomnographic (PSG) profile in drug-naïve Parkinson's disease

OBJECTIVE: We studied the changes in Polysomnographic (PSG) profile in drug-naïve patients of Parkinson's disease (PD) who underwent evaluation with sleep overnight PSG. MATERIALS AND METHODS: This prospective study included 30 with newly diagnosed levodopa-naïve patients with PD, fulfilling the UK-PD society brain bank clinical diagnostic criteria (M:F = 25:5; age: 57.2 ± 10.7 years). The disease severity scales and sleep related questionnaires were administered, and then patients were subjected to overnight PSG. RESULTS: The mean duration of illness was 9.7 ± 9.5 months. The mean Hoehn and Yahr stage was 1.8 ± 0.4. The mean Unified Parkinson's Disease Rating Scale (UPDRS) motor score improved from 27.7 ± 9.2 to 17.5 ± 8.9 with sustained usage of levodopa. Nocturnal sleep as assessed by Pittsburgh Sleep Quality Index (PSQI) was impaired in 10 (33.3%) patients (mean PSQI score: 5.1 ± 3.1). Excessive day time somnolence was recorded in three patients with Epworth Sleepiness Scale (ESS) score ≥ 10 (mean ESS score: 4.0 ± 3.4). PSG analysis revealed that poor sleep efficiency of <85% was present in 86.7% of patients (mean: 68.3 ± 21.3%). The latencies to sleep onset (mean: 49.8 ± 67.0 minutes) and stage 2 sleep (36.5 ± 13.1%) were prolonged while slow wave sleep was shortened. Respiration during sleep was significantly impaired in which 43.3% had impaired apnoea hyperpnoea index (AHI) ≥5, mean AHI: 8.3 ± 12.1). Apnoeic episodes were predominantly obstructive (obstructive sleep apnea, OSA index = 2.2 ± 5.1). These patients had periodic leg movement (PLM) disorder (56.7% had PLM index of 5 or more, mean PLMI: 27.53 ± 4 9.05) that resulted in excessive daytime somnolence. CONCLUSIONS: To conclude, sleep macro-architecture is altered in frequently and variably in levodopa-naïve patients of PD and the alterations are possibly due to disease process per se.